Chernobyl Disaster Worst Nuclear accident in 20 th century IMPACTS AND LESSONS [ID4115: Bioremediation of Soil and Water Resources, Fall 2013] Sandipan Dasgupta 4 th year, Integrated BS-MS, 10MS12 Department of Biological Sciences 1

April 26, 1986 : Pripyat, UKRAINE  Chernobyl Nuclear power plant 1.  A power surge in Reactor # 4.  Attempted Emergency Shutdown.  Fire in the vessel.  Exposed graphite moderator to air.  Large scale ignition of graphite.  Released radionuclides 2 in atmosphere.  Substantial radioactivity detected all over Europe. Notes: 1. Nuclear power plant: Where power is generated by exothermic fission reactions 2. Radionuclides: Atoms with unstable nuclei, excess energy and emit radiation. 2

Immediate effects  Large scale fire.  Official casuality: 31 1 (!!)  Reactor burned for ~10 days.  Radionuclides released: Ba, Kr, Cs, Pu, Np. 2  Countries affected: Whole Europe, worst hit Belarus, Ukarine, Russia. 1 1 Health effects of Chernobyl: IPPNW, April KASHPAROV, V.A., et al., Territory contamination with the radionuclides representing the fuel component of Chernobyl fallout, Sci. Total Environ. 317 (2003) 105– INSAG, Summary Report on the Post-accident Review Meeting on the Chernobyl Accident, Safety Series No. 75-INSAG-1, IAEA, Vienna (1986) 3 3

Long term effects  Social: More than 350,700 people evacuated, many died later.  Political: Questions over using nuclear energy.  Environmental: Unprecented release of harmful radionuclides in atmosphere (Soil, air, water) Ref: Chernobyl source term, atmospheric dispersion, and dose estimation, Energy Citations Database, 1 November

Impact on environment: Soil  Soil: Direct contact with various living forms  Increase in heavy metal concentration in soil.  Damage to microorganisms, Altered biodiversity structure.  Altered soil biodiversity, 1 DE CORT, M., Atlas of Caesium Deposition on Europe after the Chernobyl Accident, Rep , Office for Official Publications of the European Communities, Luxembourg (1998). 1 5

Impact on environment: Agriculture  Caesium, Strontium, Iodine: Mobile in environment 1.  High Cs and Iodine concentration in French cows in 1986/  Leach to groundwater column.  Loss of nutritional value in plants.  Bioaccumulation. [3] 1 HOWARD, B.J., The concept of radioecological sensitivity, Radiat. Prot. Dosim. 92 (2000) 29–34 2 BERESFORD, N.A., et al. Environ. Sci. Technol. 34 (2000) 4455– SHESTOPALOV, V.M.at al, Environ. Sci. Pollut. Res. Special issue 1 (2003) 39–47. 6

Impact on environment: Forest  Nuclides with long half lives: Cs, Pu, Sr.  Substantial contamination in Belarus, Ukraine, Russian Federation.  Radiation doses to workers in paper industry in Russia. 1 1 AVILA, R., et al., NATO Science Series, Vol. 58, Kluwer, Dordrecht (1999) 173–183. 7

Impact on environment: Water  Radioactivity found MORE in CLOSED Lake systems.  Bioaccumulation observed in fishes in Belarus 1.  Adsorption to fine particles affect the mobility and bioaccumulation 2.  Contamination can also occur by run off from the soil 3.  Adsorbed radionuclides can settle at the bed 4.  Ground water contamination is not very significant due to rapid decay 5. 1 KRYSHEV, I.I. et al, USSR Academy of Sciences, Moscow (1990) 116– VOITSEKHOVITCH, O.V, Maps of Cs-137 in the Bottom Sediments of the Dnieper Reservoirs, Ukrainian Hydro meteorological Institute, Kiev (1997) 3 SAXÈN, R., ILUS, E., Discharge of 137Cs and 90Sr by Finnish rivers to the Baltic Sea in 1986–1996, J. Environ. Radioact. 54 (2001) 275– HILTON J et al, Sci. Total Environ. 129 (1993) 253– Official report of Chernobyl impact, IAEA, Vienna 8

Impact on Human Exposure pathways External Internal Clouds Soil Inhalation of cont. air Ingestion of cont. fishes Ref: IAEA, Vienna 9

 Over 6000 thyroid cancer cases till May be due to radioactive Iodine (??)  Infrequent soild tumours, birth defects has decreased 1.  Increased concentration of radionuclides in the tissue.  Exaggerated mental behaivor due to radiation.  Unprecedented Abortion requests in Greece 2. (!!) Impact on Human 1 Health effects of Chernobyl: IPPNW, April The victims of Chernobyl in Greece: induced abortions after the accident. Br Med J (Clin Res Ed) October 31; 10

What could be done?  Accident occurred solely due to human error.  Have proper Standard Operating Procedures (SOP) for both normal and emergency situations.  Monitor Moderator Efficiency.  Proper Waste Management.  Identify the wastes.  Maintain an exclusion zone.  Monitor constantly. 11

 Comprehensive risk assessment.  Adequate methods, equipment, staff selection and monitoring.  Development of an exhaustive waste management programme.  Proper rehabilitation of waste exclusion zone. IAEA Recommendations 12

Thank you for listening 13